Work in the future will continue in two main areas (1) close tracking of normal and mutant Salmonella typhimurium in defined concentration gradients of attractants will be employed to further define the chemotactic behavior of these bacteria, (2) A rapid quantitative assay of response will be used to investigate the role of 3',5' cyclic AMP in chemotactic response. This type of work will continue and further investigations directed at a molecular understanding of chemotaxis will be performed.